Phoenix, Arizona Revisions
MILEPOST 1091
Phoenix's forecast for Thursday has moved 9°F colder
100°F in the 20260913T06:00Z run, 91°F in the 20260915T00:00Z — the 2nd-largest revision of the 4 cities on the roster that moved at all. The current run's 10th-to-90th percentile spread at that hour is 16°F.
Successive cycles do not merely refresh a forecast; they leave a trail. For Thursday, September 17 at 00Z in Phoenix, that trail runs from 99.6°F in the 20260913T06:00Z cycle to 90.7°F in the 20260915T00:00Z — a move of -8.9°F across 8 runs.
The change is about half the run's 10th-to-90th percentile spread, so the earlier forecast is still inside the current range of outcomes.
Model NBM-QMD, via api.weather.city /v1/history. Percentiles are the same run's own.
The numbers in this piece, with what they are measured against
| forecast revision for Thursday at 00Z api.weather.city /v1/history (nbm-qmd) |
-8.9 °F | normal 0.0 °F · 2 of 4 8 synoptic cycles |
| 10th-to-90th percentile spread at that hour api.weather.city (nbm-qmd) |
16.2 °F | normal 8.9 °F current run |
- Milepost
- 1091 · laid 2026-09-15T10:25:13Z
- Model
- nbm-qmd · cycle 20260915T00:00Z
- Desk
- revision v1
- Method
- the same valid time read from successive synoptic cycles; the move is last run minus first run
- Source
- https://api.weather.city/v1/history
- Digest
- 004ebc0dcdf1048a283d33e970f6dac88757b091e0ae554fed6cff9ee876ddb1
- Machine
- JSON